JP2024014402A - Inverter device installation structure, electric compressor - Google Patents

Abstract

[Problem] Even when an inverter device in which a power semiconductor element and a circuit board are modularized in advance is attached to a cooling member, the stress generated at the bonded portion between the terminal of the power semiconductor element and the circuit board is alleviated, Provided is an inverter device mounting structure and an electric compressor that can avoid or reduce electrical connection failures. SOLUTION: In an inverter device mounting structure 10, an inverter device 9 includes a power semiconductor element 63, a circuit board 8 disposed facing a first surface US of the power semiconductor element 63, and a circuit board 8. and a conductive adhesive 90 that electrically fixes the terminal 63C of the power semiconductor element 63, and a movement restriction member 100 that maintains the power semiconductor element 63 and the circuit board 8 at a predetermined distance. The second surface DS of the power semiconductor element 63 is opposed to the cooling member 23 via the material 201, and the circuit board 8 is attached to the cooling member 23. [Selection diagram] Figure 3

Description

The present invention relates to a mounting structure for an inverter device and an electric compressor.

BACKGROUND ART Conventionally, as an electric compressor used in an air conditioner for a vehicle, an inverter-integrated electric compressor is used, in which an inverter device is attached to a casing in which a motor is housed. Further, in this case, an inverter device in which a circuit board and an inverter circuit section including a power semiconductor element are modularized is often used.

Specifically, in the electric compressor described in Patent Document 1, a plurality of power semiconductor elements (power modules) are fixed in advance to one installation plate with screws, and the installation plate and the circuit board (inverter control board) are connected together. They are integrated at the sub-line to form an inverter circuit section. The inverter circuit section is removably attached to the circuit accommodating section of the housing with bolts. Since the casing functions as a cooling member by circulating a low-temperature gas refrigerant inside it, heat exchange progresses due to the close contact between the installation plate and the casing, and the power module is configured to radiate heat.

Furthermore, a method of fixing a power semiconductor element to a housing without fastening screws is also known (see, for example, Patent Document 2). The electric compressor disclosed in Patent Document 2 discloses a configuration in which a leaf spring is arranged as an elastic body between the guide part and the IGBT when the IGBT is housed inside the guide part. The guide member urges the IGBT 20 toward the housing, which is a cooling member, via this leaf spring.

As described above, conventionally, in order to improve the heat dissipation of a power semiconductor element, it has been common to apply an external force such as a screw or a leaf spring to press the semiconductor element against the casing, which is a cooling member.

JP 2019-143603 Publication Patent No. 5644706

However, in particular, in an inverter device in which a circuit board and an inverter circuit section are modularized as in Patent Document 1, the power semiconductor element or the circuit board is pressed against the casing in order to dissipate heat from the power semiconductor element. If it is fixed, there is a problem in that a load is applied to the electrical connection between the power semiconductor element and the circuit board.

Specifically, in the inverter device, the terminals (leads) of the power semiconductor elements and the wiring of the circuit board are electrically fixed in the sub-line in advance using a conductive adhesive such as solder.

In this state, when the power semiconductor device or the circuit board is fastened to the casing with screws and pressed, the power semiconductor device and the circuit board receive a reaction force from the casing corresponding to the fastening force. This reaction force acts on an electrically fixed part such as solder, and stress is generated in the fixed part. Especially when the conductive adhesive is solder, cracks may occur in the bonded portion (solder joint) due to stress due to variations in quality and shape of the bonded portion. As a result, there is a concern that a connection failure may occur in the inverter device.

For example, a similar problem occurs when a power semiconductor element is biased against a housing by a leaf spring as in Patent Document 2.

In view of such circumstances, the present invention provides that even when an inverter device in which power semiconductor elements and a circuit board are modularized in advance is attached to a cooling member, the fixed portion between the terminal of the power semiconductor element and the circuit board is fixed. The present invention aims to provide an inverter device mounting structure and an electric compressor that can alleviate the stress generated in the inverter and avoid or reduce electrical connection failures.

The present invention is an inverter device mounting structure for attaching an inverter device to a cooling member, wherein the inverter device includes a power semiconductor element and a circuit board disposed facing a first surface of the power semiconductor element. a conductive adhesive that electrically fixes the circuit board and the terminal of the power semiconductor element; and a movement restriction member that maintains the power semiconductor element and the circuit board at a predetermined distance. , the second surface of the power semiconductor element is opposed to the cooling member via a heat dissipation material, and the circuit board is attached to the cooling member. .

Further, the present invention provides an electric compressor having the above-mentioned inverter device mounting structure and having a motor built in the housing, wherein the cooling member is a part of the housing. This relates to an electric compressor.

According to the present invention, even when an inverter device in which power semiconductor elements and circuit boards are modularized in advance is attached to a cooling member, stress generated at the fixed portion between the terminals of the power semiconductor elements and the circuit board can be reduced. An excellent effect can be achieved in that it is possible to provide an inverter device mounting structure and an electric compressor that can alleviate or reduce electrical connection failures.

1 is a vertical cross-sectional view showing an outline of an electric compressor according to an embodiment of the present invention. FIG. 1 is a circuit block diagram of an electric compressor according to an embodiment of the present invention. FIG. 1 is a diagram schematically showing an inverter circuit section of the present embodiment, and is (A) a schematic cross-sectional view, (B) an external perspective view of a power semiconductor element, and (C) a schematic cross-sectional view of a power semiconductor element. FIG. 2 is a schematic cross-sectional view illustrating a method of assembling an inverter device according to the present embodiment. FIG. 3 is a schematic cross-sectional view illustrating a method of attaching the inverter device according to the present embodiment. FIG. 2 is a schematic cross-sectional view illustrating a method of assembling the electric compressor of this embodiment. FIG. 2 is a schematic cross-sectional view illustrating the mounting structure of the inverter device according to the present embodiment. FIG. 2 is a diagram illustrating the mounting structure of the inverter device according to the present embodiment, in which (A) a cross-sectional schematic diagram showing the mounting structure, (B), (C) a plan view of a power semiconductor element, and (D) a cross-section showing the mounting structure. It is a schematic diagram. They are (A) an external perspective view of a power semiconductor module and (B) a schematic cross-sectional view of the present embodiment. FIG. 2 is an external perspective view illustrating a method of assembling the inverter device according to the present embodiment. FIG. 2 is a cross-sectional schematic diagram illustrating a method of attaching an inverter device according to the present embodiment. FIG. 2 is a cross-sectional schematic diagram illustrating a method of attaching an inverter device according to the present embodiment.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 12. 1 to 12 are examples of embodiments of the present invention, and in the figures, parts given the same reference numerals represent the same configurations. Further, in each figure, some components are omitted as appropriate to simplify the drawings. Further, in each figure, the shapes and dimensions of some structures are appropriately exaggerated.

<Overall configuration of electric compressor>
With reference to FIG. 1, the overall configuration of an electric compressor 1 of this embodiment will be described. This figure is a vertical cross-sectional view showing an outline of an electric compressor 1 having a mounting structure for an inverter device 9 according to the present embodiment, and for convenience of explanation, only the main components are schematically shown.

The electric compressor 1 of this embodiment is a so-called inverter-integrated electric compressor, and constitutes a part of a refrigerant circuit of a vehicle air conditioner that air-conditions the interior of a vehicle (not shown). The electric compressor 1 includes a housing 2, a motor 3 built into the housing 2, a compression mechanism 5 driven by a rotating shaft 4 of the motor 3, an inverter device 9, and the like. The inverter device 9 includes at least a circuit board (printed board) 8 and an inverter circuit section 6 for driving the motor 3. In this example, the inverter device 9 includes a filter circuit section 7 for absorbing high frequency components of the switching current, and an inverter circuit section 6 for driving the motor 3. It includes a control unit 16 and the like.

The housing 2 includes, for example, a housing 21 that is a housing portion for the motor 3, a circuit housing portion 22, and a lid member 25 that covers the circuit housing portion 22. The housing 21 accommodates the motor 3, the rotating shaft 4, and the compression mechanism 5, and the circuit housing section 22 houses the inverter device 9 (inverter circuit section 6, filter circuit section 7, inverter control section 16, circuit board 8, etc.). be accommodated.

The circuit housing section 22 includes, for example, a first space 221 and a second space 222. The first space 221 is a space adjacent to the housing 21 via the partition wall 23 at one end in the axial direction of the rotating shaft 4 of the motor 3, and accommodates the inverter circuit section 6. The second space 222 is a space that protrudes outward in the stator radial direction of the motor 3 from the housing 21, and accommodates the filter circuit section 7. In this embodiment, as an example, an inverter circuit section 6 and a filter circuit section 7 are configured on one circuit board 8, and the inverter circuit section 6 and filter circuit section 7 are housed inside the housing 2 (circuit housing section 22). A circuit board 8 is removably attached to the housing 2. The circuit accommodating portion 22 has an opening 24 on the opposite surface of the partition wall 23, and is closed by a lid member 25 so as to be openable and closable. Note that although the electric compressor 1 is shown in each figure in this embodiment with the circuit housing part 22 facing upward, in reality, as a vehicle air conditioner, it is placed horizontally so that the circuit housing part 22 is on one side. placed in the direction. In this embodiment, for convenience of explanation, the directions in the electric compressor 1 are defined as the circuit housing part 22 side is upward and the motor 3 side is downward, and the direction of the rotating shaft 4 of the motor 3 in each configuration (motor axial direction) is defined as "Height direction".

The inverter device 9 is configured such that each electronic component constituting the inverter circuit section 6 and the filter circuit section 7 is mounted on a circuit board (printed board) 8 or electrically connected. In this embodiment, a case is illustrated in which an inverter circuit section 6 and a filter circuit section 7 are integrally provided (modularized) on one circuit board 8 to form an inverter device 9. Specifically, electronic components constituting the inverter control unit 16 are directly mounted (mounted) on the first surface Sf1 of the circuit board 8 and electrically connected. The inverter circuit section 6 is provided in a predetermined region on the second surface Sf2 of the circuit board 8, and the filter circuit section 7 is provided in another predetermined region on the same second surface Sf2.

In the inverter circuit section 6, terminals 63C of the plurality of power semiconductor elements 63 constituting the inverter circuit section 6 are electrically connected and fixed to the circuit board 8. In the filter circuit section 7, filter circuit components 70 such as a noise filter 72 and a smoothing capacitor 71 constituting the filter circuit section 7 are integrated by, for example, an insulating resin section 73, and are directly mounted (mounted) on the circuit board 8 and electrically connected to the circuit board 8. Connect to

Note that the circuit board 8 is not limited to this example, and the circuit board 8 may be separated into a circuit board for the inverter circuit section 6 and a circuit board for the filter circuit section 7. In this case, the inverter device 9 of this embodiment includes at least the inverter circuit section 6 and a circuit board (for the inverter circuit section 6) that is electrically connected to the inverter circuit section 6, and has a configuration in which both are integrated. say.

The motor 3 is composed of a three-phase synchronous motor (brushless DC motor), and the compression mechanism 5 is, for example, a scroll type compression mechanism. The compression mechanism 5 is driven by the rotating shaft 4 of the motor 3, compresses the refrigerant, and discharges it into the refrigerant circuit. A low-temperature gas refrigerant drawn from an evaporator (also referred to as a heat absorber), which also constitutes a part of the refrigerant circuit, flows through the housing 21 . Therefore, the inside of the housing 21 is cooled, and accordingly, the partition wall 23 forming a part of the lower part (bottom part 22B) of the circuit housing part 22 is also cooled by the low-temperature gas refrigerant.

A power semiconductor element (power semiconductor element) 63 of the inverter circuit part 6 is tightly attached to the upper surface 23U of the partition wall 23 (bottom part 22B of the circuit housing part 22 on the first space 221 side) with a heat dissipation material 201 interposed therebetween. The heat dissipating material 201 is, for example, paste-like silicon, a material that hardens with one or two liquids under conditions such as room temperature, high temperature, and humidity, or a material with low fluidity such as silicone grease. The insulating resin part 73 of the filter circuit part 7 is in close contact with the upper surface of the bottom part 22B of the circuit accommodating part 22 on the second space 222 side with a heat dissipating material (for example, an insulating sheet) 302 interposed therebetween. The circuit board 8 is fixed to the housing 2 (bottom portion 22B of the circuit housing portion 22) with bolts 85.

FIG. 2 is a circuit diagram schematically showing an electric circuit for controlling the motor drive of the electric compressor 1. As shown in FIG. The inverter circuit unit 6 includes a plurality of power semiconductor elements 63 (here, as an example, three sets of six in total) each including a switching element (for example, an IGBT) 61 and a free wheel diode 62. Further, the filter circuit section 7 includes a filter circuit component 70. In this example, the filter circuit component 70 includes a smoothing capacitor 71 that smoothes the power supplied to the inverter circuit section 6, and a coil and a capacitor that constitute a noise filter 72.

Electric power from a power source 12 is supplied to the inverter device 9 via a high-power connector 13 , and is supplied to the inverter circuit section 6 via a noise filter 72 and a smoothing capacitor 71 .

Further, low voltage power is supplied from the air conditioning control device 18 of the vehicle to the inverter control unit 16 via the control signal connector 19. The inverter control unit 16 is composed of a microcomputer (processor) mounted on the circuit board 8, and includes a motor control unit (not shown), a PWM control unit, a gate driver for the power semiconductor element 63, etc., and responds to commands from the outside. Based on this, switching control of each power semiconductor element 63 of the inverter circuit section 6 is performed. The inverter control unit 16 also has a function of transmitting the driving state of the motor 3 to the outside.

In the inverter circuit section 6, the direct current from the power source 12 is converted into pseudo three-phase alternating current, and the converted alternating current is output from the inverter device 9. This output is supplied to each winding 3a of the motor 3 via the motor-side connection terminal 11, whereby the motor 3 is rotationally driven and compression by the compression mechanism 5 is performed.

<Mounting structure of inverter device/first embodiment>
The mounting structure 10 for the inverter device 9 will be explained with reference to FIG. FIG. 3(A) is a schematic cross-sectional view showing the mounting structure 10 between the inverter device 9 and the cooling member 23, and FIG. Figure (C) is a schematic cross-sectional view of the power semiconductor element 63. Note that in FIG. 3 and subsequent figures (excluding FIG. 6), the inverter circuit section 6 portion of the inverter device 9 is extracted and illustration of other components (filter circuit section 7, etc.) is omitted.

As shown in FIG. 3A, the inverter device 9 of this embodiment electrically fixes the power semiconductor element 63, the circuit board 8, and the circuit board 8 and the terminals 63C of the power semiconductor element 63. It has a conductive adhesive 90 and a movement regulating member 100.

The inverter circuit section 6 constituting the inverter device 9 includes a plurality of (six in this case) power semiconductor elements 63 constituting arms of each phase of a three-phase inverter circuit as shown in FIG. 3(B). As shown in (A), it is electrically connected to the circuit board 8.

As shown in Figures (A) and (C), each power semiconductor element 63 includes a semiconductor chip 63S in which a switching element (for example, IGBT) 61 and a free wheel diode 62 (see Figure 2) are connected. , is a molded element placed on one surface (upper surface) of the heat sink 64 and housed in one resin package 63P. The resin package 63P has a substantially rectangular parallelepiped outer shape, and in the following explanation, the two surfaces that are parallel (horizontal) to the cooling member 23 when placed on it are referred to as the upper surface US and the lower surface DS of the power semiconductor element 63. The remaining four surfaces are called side surfaces SS.

Three terminals (leads) 63C of the power semiconductor element 63 are led out from the side surface SS of the resin package 63P in a direction horizontal to the heat sink 64, and are bent upward into a substantially L-shape in cross-sectional view. The other surface (lower surface) of the heat sink 64 is exposed on the lower surface DS of the resin package 63P. Note that this embodiment employs a conventionally known power semiconductor element 63, and the resin package 63P is provided with a fixing hole 63H that penetrates from the upper surface US to the lower surface DS. The fixing hole 63H is a hole that has conventionally been used as a screw insertion hole when screwing the power semiconductor element 63 to a circuit board or other board. It is hollowed out in a circular shape corresponding to the . However, in this embodiment, the power semiconductor element 63 and other members are not fastened with screws.

Referring to FIG. 3(A), circuit board 8 is arranged such that its second surface Sf2 faces the first surface (upper surface US) of power semiconductor element 63. Here, a movement restriction member 100 is arranged between the first surface US of the power semiconductor element 63 and the second surface Sf2 of the circuit board 8 to maintain a predetermined distance t1 between the two. In this example, the movement regulating member 100 has a small-diameter, substantially cylindrical substrate engaging portion 103 stacked on a large, substantially cylindrical pedestal portion 104 such that the axial directions of both cylinders are in the same direction. It has a shape. The lower surface (bottom surface) of the pedestal section 104 becomes a package contacting section 101 that comes into contact with the upper surface US of the power semiconductor element 63 (same as the upper surface of the resin package 63P, hereinafter the same), and the substrate engaging section 103 that protrudes from the pedestal section 104 The stepped portion (shoulder portion) becomes a board abutting portion 102 that comes into contact with the circuit board 8. The board engaging portion 103 is a portion that is inserted into an engaging hole 88 provided in the circuit board 8 and engages with the circuit board 8 . The diameter of the engagement hole 88 is larger than the diameter of the substrate engagement part 103 and smaller than the diameter of the pedestal part 104. As a result, the board engaging part 103 can be inserted into the engaging hole 88, and the second surface Sf2 of the circuit board 8 comes into contact with the board abutting part 102 with the board engaging part 103 inserted.

The movement regulating member 100 is made of a hard resin material that is difficult to deform during normal (general) use (operation) of the electric compressor 1 (for example, PPS (polyphenylene sulfide), PBT (polybutylene terephthalate), or other super engineering materials). The package contacting portion 101 of the movement regulating member 100 is placed on the upper surface US of the power semiconductor element 63, and the substrate contacting portion 102, which is a shoulder portion, is By placing the circuit board 8 thereon, the power semiconductor element 63 and the circuit board 8 are maintained at a distance t1 in the height (vertical) direction (motor axis direction).

As shown in FIG. 3B, in this example, the six power semiconductor elements 63 are each independently connected (fixed) to the circuit board 8. In this case, it is desirable that the movement regulating member 100 be disposed on the upper surface US of each of the six power semiconductor elements 63. However, the power semiconductor element 63 without the movement regulating member 100 may be included. Further, in one inverter device 9, the shapes of the plurality of movement regulating members 100 may be the same or different, but at least the height t1 of the pedestal portion 104 in the motor axis direction is the same.

The movement restriction member 100 functions as a spacer between the power semiconductor element 63 and the circuit board 8, maintains the distance t1 between the two, and restricts them from moving in a direction closer to each other than the distance t1. Furthermore, by inserting the board engaging portion 103 into the engaging hole 88, the relative movement of the movement regulating member 100 and the circuit board 8 in the horizontal direction (horizontal direction in the drawing) perpendicular to the motor axis direction is also restricted.

Here, the movement regulating member 100 engages with the circuit board 8, but is not fixed or fixed and is allowed to separate. Further, in the movement regulating member 100 of this example, the pedestal portion 104 is placed on the upper surface US of the power semiconductor element 63, but is not fixed or fixed. The movement regulating member 100 does not apply external force to the power semiconductor element 63 to press it downward (towards the cooling member 23), such as by fastening with screws or pressing with a leaf spring, but when the power semiconductor element 63 is in the circuit. Movement of the substrate in the 8 direction is restricted.

Note that the movement regulating member 100 may have the shape shown in the drawings as long as it maintains the distance t1 between the power semiconductor element 63 and the circuit board 8 in the motor axis direction and prevents them from moving in a direction closer to each other than the distance t1. However, the present invention is not limited to this, and, for example, only the pedestal portion 104 (without the substrate engaging portion 103) may have a shape.

The circuit board 8 is provided with the same number of terminal insertion holes 83 (for example, 18) as the terminals 63C, into which the tips of the terminals (leads) 63C of the power semiconductor element 63 can be inserted. The tip of the terminal 63C is inserted into the terminal insertion hole 83 from the second surface Sf2 of the circuit board 8, and led out to the first surface Sf1. Then, in the vicinity of the terminal insertion hole 83, the terminal 63C and the wiring of the circuit board 8 are fixed and fixed using a conductive adhesive 90 so that the wiring is electrically connected to the terminal 63C. An area where the conductive adhesive 90 is applied and where the terminal 63C and (the wiring of) the circuit board 8 are fixed is referred to as a fixing portion 91. The conductive adhesive 90 is solder in this example, but is not limited to this, and may be a conductive paste. The circuit board 8 and the power semiconductor element 63 are connected only by the terminal 63C formed by the conductive adhesive 90 and the fixed portion 91 of the circuit board 8.

As described above, in the inverter device 9 of this embodiment, the power semiconductor element 63 and the circuit board 8 are integrated (modularized) in advance (by sub-line) by the fixing portion 91 (only), and in this state It is accommodated in the circuit accommodating portion 22 of the housing 2. Specifically, the inverter circuit section 6 is housed in the first space 221 of the circuit housing section 22, and the lower surface DS (heat sink 64) of the power semiconductor element 63 and the partition wall 23 are arranged to face each other with the heat sink 201 interposed therebetween. . Then, due to the weight of the inverter device 9, the lower surface DS of the power semiconductor element 63 comes into close contact with the heat dissipating material 201, and comes into surface contact with the partition wall 23 via the heat dissipating material 201.

The heat dissipation material 201 is a means for efficiently transmitting heat generated in the heat dissipation plate 64 to the cooling member 23, and also serves as a surface of the lower surface DS of the power semiconductor element 63 including the heat dissipation plate 64 and the upper surface 23U of the cooling member 23. It also functions as a means to absorb shape variations (such as unintended irregularities) and assembly tolerances.

On the other hand, it is desirable that the heat dissipation material 201 is made of a material that makes the reaction force (repulsive force) generated against the power semiconductor element 63 as small as possible when the power semiconductor element 63 is placed thereon.

For these reasons, a material is selected for the heat dissipating material 201 that has a certain degree of fluidity and/or flexibility (viscosity) but has low elasticity. Specifically, as described above, the heat dissipating material 201 is, for example, paste-like silicon, a material that hardens in one or two parts under conditions such as room temperature, high temperature, and humidity, or a material with low fluidity such as silicone grease. etc.

In this embodiment, there is no means for pressing the power semiconductor element 63 against the partition wall 23 by an external force, such as conventional screws or leaf springs. In other words, the power semiconductor element 63 can receive a smaller reaction force from the partition wall 23 than in the prior art. As a result, the stress generated in the fixed portion 91 between the terminal 63C of the power semiconductor element 63 and the circuit board 8 can be alleviated, and connection failures such as cracks in the conductive adhesive 90 can be avoided.

Further, a movement regulating member 100 is provided between the circuit board 8 and the power semiconductor element 63 to maintain the distance t1 between the two. If the circuit board 8 is particularly integrated with the filter circuit section 7, the weight of the circuit board 8 increases, so when the inverter device 9 is housed and installed in the circuit housing section 22, power semiconductor elements (unintentionally) may be removed. There is a possibility that an excessive load will be applied to the terminal 63C of the terminal 63 and the fixed portion 91. Furthermore, the present invention is not limited to this, and there is a possibility that an external force (particularly an upward or downward force) is applied to the circuit board 8 or the power semiconductor element 63. In this embodiment, the movement regulating member 100 can prevent the power semiconductor element 63 and the circuit board 8 from moving toward each other in the axial direction of the motor, thereby preventing excessive loads from concentrating on the terminals 63C and the fixed portions 91. It can be avoided.

In the case 2, a low-temperature gas refrigerant flows inside a housing 21 that accommodates the motor 3, and a partition wall 23 that forms a boundary with the housing 21 functions as a cooling member. Therefore, the heat radiating plate 64 comes into close contact with the partition wall 23, which is a cooling member, through the heat radiating material 201, heat exchange progresses, and the power semiconductor element 63 efficiently radiates heat.

The circuit board 8 is removably attached to the partition wall 23 (casing 2) with bolts 85. Here, as shown in FIG. 3A, in this embodiment, in addition to the above-mentioned movement regulating member (hereinafter referred to as a first movement regulating member) 100, another movement regulating member (hereinafter referred to as a second movement regulating member) is used. It has 110. The second movement regulating member 110 is a member that maintains the cooling member (partition) 23 and the circuit board 8 at a predetermined distance t2, and has a cooling member contact portion 111 and a board contact portion 112. In this example, the movement regulating member 110 is a sleeve component that is hollow inside and into which the bolt 85 can be inserted. The lower open end of the sleeve component becomes a cooling member abutting section 111 that comes into contact with the cooling member 23, and the upper open end of the sleeve component becomes a board abutting section 112 that comes into contact with the circuit board 8.

The second movement regulating member 110 is also made of a hard resin material (for example, polycarbonate, engineering plastic, super engineering plastic, etc.) that does not substantially deform (is difficult to deform) during normal (common) use (operation) of the electric compressor 1. ) and metal materials.

The height (length in the motor axis direction) t2 of the second movement restriction member 110 is greater than the sum of the height t3 of the power semiconductor element 63 and the height t1 of the pedestal portion 104 of the first movement restriction member 100. That is, when the inverter device 9 is attached to the cooling member 23 (when housed in the circuit accommodating part 22), the circuit board 8 is fastened and fixed to the cooling member 23 by the bolts 85, but due to the presence of the second movement restriction member 110. The circuit board 8 and the power semiconductor element 63 are not pushed toward the cooling member 23, and the reaction force from the cooling member 23 can be kept to a minimum.

In this way, the second movement restricting member 110 functions as a spacer between the cooling member 23 and the circuit board 8, maintains the distance t2 between the two, and restricts them from moving in a direction closer to each other than the distance t2.

The second movement regulating member 110 is arranged between the circuit board 8 and the cooling member 23, but is not fixed or fixed to either of them. Note that the second movement regulating member 110 and the circuit board 8 may be able to be engaged by providing an engagement protrusion or the like on the board abutting portion 112 and providing an engagement hole at a corresponding position on the circuit board 8. In addition to this, or in place of this, an engaging protrusion or the like is provided on the cooling member abutting portion 111 and an engaging hole is provided at a corresponding position on the cooling member 23 to cool the second movement regulating member 110. The member 23 may be engageable.

Further, the second movement restriction member 110 may have the shape shown in the figure if it is configured to maintain the cooling member 23 and the circuit board 8 at a predetermined distance t2 in the motor axis direction and restrict movement of the two toward each other. Not exclusively. For example, the second movement regulating member 110 may be a sleeve component into which the bolt 85 is not inserted, or may be a columnar member whose interior is not hollow (solid). In this case, the second movement regulating member 110 is arranged at a different position from the bolt 85, such as adjacent to the bolt 85.

Further, in one inverter device 9, a plurality of second movement regulating members 110 are arranged. The shapes of the plurality of second movement restriction members 110 may be the same or different, but a plurality (at least two) of the second movement restriction members 110 having at least the same height t2 in the motor axial direction are arranged. It is desirable that the plurality of second movement regulating members 100 be arranged at equal intervals as much as possible so as to surround, for example, six power semiconductor elements 63.

The second movement regulating member 110 supports the circuit board 8 to which the power semiconductor element 63 is electrically fixed, and its height t2 is such that when the circuit board 8 is supported, the power semiconductor element 63 is The lower surface DS of the power semiconductor element 63 and the upper surface 23U of the cooling member 23 are not in direct contact with each other, and the lower surface DS of the power semiconductor element 63 is set to maintain a state in which it directly contacts only the heat dissipation material 201. ing.

As a result, when the inverter device 9 is housed in the circuit accommodating portion 22 as shown in FIG. A very small gap is created by the member 110. In this embodiment, a heat dissipating material 201 is arranged between the heat dissipating plate 64 and the cooling member 23 to fill the gap between the two, and through this, the heat dissipating plate 64 and the cooling member 23 are indirectly connected to each other so as to have a sufficient surface area. bring into contact. The gap (coating thickness of the heat dissipating material 201) is, for example, 0.5 mm to 10 mm, preferably 0.5 mm to 5 mm, preferably 0.5 mm to 3 mm, and more preferably 0.5 mm to 2 mm. . Alternatively, the gap (coating thickness of the heat dissipating material 201) may be, for example, 0.5 mm to 1.5 mm, 1.0 mm to 1.5 mm, 1.0 mm to 1.5 mm, 1.0 mm to 2.0 mm, etc. It's okay.

In other words, the heat dissipation material 201 is a means for efficiently transmitting the heat generated in the heat dissipation plate 64 to the cooling member 23 , and in addition, the heat dissipation material 201 is a means for efficiently transmitting heat generated in the heat dissipation plate 64 to the cooling member 23 . In addition to filling the extremely small gap that occurs between the heat dissipating plate 64 and the upper surface 23U of the cooling member 23 and the lower surface DS of the power semiconductor element 63 and the upper surface 23U of the cooling member 23, it also absorbs variations in surface shape (such as unintended irregularities) and assembly tolerances. It also functions as a means.

Although the second movement restricting member 110 prevents the power semiconductor element 63 and the circuit board 8 from being pushed in the direction of the cooling member 23 by exceeding their own weight, variations in assembly tolerances and the power semiconductor element 63 Also, due to variations in the surface shape of the opposing surface of the circuit board 8, some pushing may occur. In this case, if a material with a large elastic force is used as the heat dissipating material 201, the reaction force from the cooling member 23 will increase, and stress may be generated in the fixed portion 91.

For these reasons, as described above, the heat dissipating material 201 is selected from a material that has a certain degree of fluidity and/or flexibility (viscosity) but has a low elastic force.

The heat dissipation material 201 fills a very small gap created between the heat dissipation plate 64 of the power semiconductor element 63 and the cooling member 23 by the second movement regulating member 110, and also covers the lower surface of the power semiconductor element 63 including the heat dissipation plate 64. The material and thickness (coating thickness) are appropriately selected in consideration of the ability to absorb surface shape variations (such as unintentional unevenness) and assembly tolerances of the DS and the cooling member 23, and the shape of the parts. The heat dissipating material 201 is desirably a material that further has insulating properties, but does not need to have any insulating properties.

Further, the heat dissipating material 201 may be any material that has fluidity when the inverter device 9 is assembled to the cooling member 23, and may be a material that can be hardened after assembly.

In this way, the mounting structure 10 for the inverter device 9 that attaches the inverter device 9 to the cooling member 23 can be realized. Further, as already stated, the cooling member 23 is a part (partition wall) of the housing 2 in which the motor of the electric compressor 1 is housed. Therefore, the mounting structure 10 for the inverter device 9 can realize an electric compressor 1 that integrally accommodates the inverter device 9 (see FIG. 1).

The second movement regulating member 110 is a columnar (cylindrical) member that is integral with the partition wall 23 (stands upright from the partition wall 23), has a threaded groove 26 at its upper end, and is fixed with a bolt 25 that is screwed into the threaded groove 26. Good too.

<How to install an inverter device/First embodiment>
A method of assembling the inverter device 9 of this embodiment and a method of attaching the inverter device 9 to the cooling member 23 will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic cross-sectional view showing a method of assembling the inverter device 9, and FIG. 5 is a schematic cross-sectional view showing, in chronological order, a method of attaching the inverter device 9 to the cooling member 23. 4 and 5, the inverter circuit section 6 portion of the inverter device 9 is extracted and illustrated, and illustration of other components (filter circuit section 7, etc.) is omitted.

First, as shown in FIG. 4A, the power semiconductor element 63 constituting the inverter circuit section 6 is held (supported) by a predetermined jig (not shown). Although one power semiconductor element 63 is shown in FIGS. 4 and 5, the inverter circuit section 6 has a plurality of (six in this example) power semiconductor elements 63. That is, the six power semiconductor elements 63 are arranged into a set of three using a jig, and the terminals 63C of each set are held in the same direction with respect to each other, and the two sets of terminals 63C are held facing each other (FIG. 3). (See (B)).

As shown in FIG. 4(B), the first position regulating member 100 is arranged on the first surface (upper surface US) of the six power semiconductor elements 63. In this example, the six power semiconductor elements 63 are each held independently by a jig, and the first position regulating member 100 is attached to the package contact portion on the upper surface US of each of the six power semiconductor elements 63. 101 are placed so that they are in contact with each other.

As shown in FIG. 8C, with a predetermined distance t1 secured by the first movement regulating member 100, the first surface (upper surface US) of the power semiconductor element and the second surface of the circuit board 8 The circuit board 8 is arranged so that Sf2 faces the circuit board 8. Engagement holes 88 are provided in a predetermined area of the circuit board 8 at positions corresponding to the board engagement portions 103 of the six first position regulating members 100 .

As shown in FIG. 2D, the board engaging portion 103 is inserted into the engaging hole 88 to bring the second surface Sf2 of the circuit board 8 into contact with the board abutting portion 102 of the first position regulating member 100. . The circuit board 8 is placed on the board abutting portion 102, which is a shoulder portion of the first movement regulating member 100, and is supported at a distance t1 from the upper surface US of the power semiconductor element 63. Although the first movement regulating member 100 is not fixed (adhered) to either the circuit board 8 or the power semiconductor element 63, the board engaging portion 103 of the first movement regulating member 100 is engaged with the circuit board 8.

The circuit board 8 is provided with a terminal insertion hole 83, and in this state, the tip of the terminal 63C of the power semiconductor element 63 is inserted through the terminal insertion hole 83 from the second surface Sf2 side of the circuit board 8. 1 to the side Sf1.

In this state, the wiring (not shown) provided on the first surface Sf1 of the circuit board 8 and the terminal 63C of the power semiconductor element 63 are electrically fixed (connected) with the conductive adhesive 90, and the fixed portion Form 91. The power semiconductor element 63 is fixed to the circuit board 8 only by the fixing part 91. In this way, the inverter circuit section 6 is assembled.

Further, although not shown here, in another region of the circuit board 8, the filter circuit components 70 constituting the filter circuit section 7 are integrated with the circuit board 8 by an insulating resin section 73 or the like. Then, the terminals (leads) of the filter circuit component 70 are led out from the second surface Sf2 of the circuit board 8 to the first surface Sf1 side through the terminal insertion holes, and It is electrically fixed (connected) to wiring (not shown) provided on the surface Sf1 to form the filter circuit section 7. In this way, the inverter device 9 in which the inverter circuit section 6 and the filter circuit section 7 are integrated (modularized) on one circuit board 8 is assembled.

Thereafter, the inverter device 9 is attached to the cooling member 23. That is, as shown in FIG. 5A, a heat dissipating material 201 is provided on the upper surface of the cooling member 23 by coating or the like. The heat dissipation material 201 is applied to the upper surface of the cooling member 23 at least at a position where it contacts the heat dissipation plate 64 of the power semiconductor element 63.

Thereafter, as shown in FIG. 5(B), the inverter device 9 is placed at a predetermined position on the cooling member 23. At this time, first, the plurality of second movement regulating members 110 are arranged at predetermined positions. In this example, the second movement regulating member 110 is a hollow sleeve component, and the cooling member 23 is moved so that its lower open end (cooling member contact portion 111) contacts the periphery of the screw hole 26 of the cooling member 23. Place it on top.

As shown in FIG. 5(C), the inverter device 9 is placed on the upper open end (board abutting portion 112) of the second movement regulating member 110, specifically, on the second surface of the circuit board 8. Place Sf2. The circuit board 8 is supported by the second movement regulating member 110, and the second surface (lower surface DS) of the power semiconductor element 63 faces the cooling member 23.

Although a gap is created between the lower surface DS of the power semiconductor element 63 and the cooling member 23 due to the second movement regulating member 110, the gap is filled by the heat dissipation material 201. Furthermore, assembly tolerances in the motor axial direction and variations in the surface shapes (irregularities, etc.) of the power semiconductor element 63 (resin package 63P and heat sink 64) and the upper surface 23U of the cooling member 23 are absorbed. Thereby, the second surface (lower surface DS, heat radiating plate 64) of the power semiconductor element 63 comes into surface contact with the upper surface of the cooling member 23 via the heat radiating material 201.

Then, as shown in FIG. 5C, bolts 85 are inserted into bolt insertion holes 86 provided in the circuit board 8 and fastened and fixed to the screw holes 26 of the cooling member 23. In this example, the second movement restricting member 110 is arranged so as to communicate with both the bolt insertion hole 86 and the screw hole 26 of the cooling member 23. That is, the bolt 85 is inserted into the second movement regulating member 110 and fastened to the screw hole 26, and the circuit board 8 is detachably fixed to the cooling member 23.

At this time, the presence of the second movement regulating member 110 prevents both the circuit board 8 and the power semiconductor element 63 from being pressed against the cooling member 23 by the strong fastening force of the bolts 85 even when fastened with the bolts 85. Ru. Furthermore, the heat dissipating material 201 is also made of a material with low elasticity. Therefore, the reaction force (upward force in the motor axial direction) from the cooling member 23 can be reduced, and the stress on the fixed portion 91 can be alleviated.

In this way, the inverter device 9 can be attached to the cooling member 23. Here, the cooling member 23 described above is a part of the casing 2 in which the motor of the electric compressor 1 is housed, as shown in FIG. Therefore, the electric compressor 1 can be assembled using the above method. That is, the inverter device 9 is manufactured by integrating the circuit board 8, the inverter circuit section 6, and the filter circuit section 7 in advance through a sub-line or the like. Then, the inverter device 9 is housed in the circuit housing section 22 defined within the housing 2, and the circuit board 8 is fixed to the housing 2 with bolts 85 using the method described above, and the electric compressor 1 is assembled.

In the inverter-integrated electric compressor 1, in order to improve the heat dissipation of the power semiconductor element 63 housed in the circuit housing part 22, the bottom part 22B of the circuit housing part 22, which is a cooling member, and the heat sink plate 64 ( It is desirable to achieve uniform and sufficient surface contact (through the heat dissipating material 201).

Conventionally, a power semiconductor element is pressed (biased) against a housing that is a cooling member using screws or a leaf spring, or a circuit board to which a power semiconductor element is fixed is pressed (biased) against a housing that is a cooling member. The heat dissipation plate and the cooling member were brought into surface contact, for example by

However, when attaching the inverter device 9 in which the circuit board 8 and the inverter circuit section 6 are integrated (modularized) in advance to the circuit housing section 22 (cooling member 23) as in this embodiment, there are problems with the above conventional method. arise.

Specifically, in this embodiment, when the inverter device 9 is housed in the circuit accommodating part 22, that is, when the power semiconductor elements 63 and the bottom part 22B of the circuit accommodating part 22 are brought into surface contact, the circuit board 8 and the power The terminal 63C of the semiconductor element 63 is fixed with a conductive adhesive 90.

Therefore, in order to improve the adhesion between the power semiconductor element 63 and the bottom part 22B of the circuit accommodating part 22, the circuit board 8 or the power semiconductor element 63 is fixed to the circuit accommodating part by fixing means such as screws or leaf springs as in the conventional method. 22, there is a problem in that stress is generated in the fixed portion 91 of the terminal 63C and the circuit board 8 due to the reaction force. In particular, when the conductive adhesive 90 is solder or the like, there may be variations in its quality and shape as the fixed part 91, and stress may cause cracks in the fixed part 91, resulting in poor bonding.

In this embodiment, while the power semiconductor element 63 and the circuit board 8 are maintained at a predetermined distance t1 in the motor axis direction by the first movement regulating member 100, the terminals 63C and the circuit board 8 are electrically connected by the conductive adhesive 90. Make the connection. In other words, even if an external force is applied that causes the circuit board 8 and the power semiconductor element 63 to approach each other in the motor axial direction after they are fixed with the conductive adhesive 90, the first movement regulating member 100 will keep the circuit board 8 and the power semiconductor element 63 close to each other. The stress on the fixed portion 91 can be alleviated without moving in a direction approaching t1 or more.

Further, when fastening the circuit board 8 to the cooling member 23 with the bolts 85, the circuit board 8 and the cooling member 23 are fastened and fixed in a state where the second movement restriction member 110 restricts the circuit board 8 and the cooling member 23 from coming closer than the distance t2. If the second movement regulating member 110 is not disposed, the circuit board 8 will be strongly pressed against the cooling member 23 by the fastening force of the bolt 85, and the reaction force will act on the fixed part 91 as stress, causing cracks to occur. becomes. In this embodiment, the circuit board 8 is prevented from being pressed against the cooling member 23 side, and this also makes it possible to relieve the stress on the fixed portion 91.

Further, the second surface (lower surface DS, heat sink 64) of the power semiconductor element 63 is made to face the cooling member 23 via the heat radiation material 201, and the circuit board 8 is attached to the cooling member 23. This heat dissipating material 201 employs a material that has a certain degree of fluidity and/or flexibility (viscosity) but has a small elastic force. Although a gap is created between the cooling member 23 and the power semiconductor element 63 due to the second movement regulating member 110, the gap is filled with the heat dissipation material 201, and the surface of the power semiconductor element 63 and the cooling member 23 is Absorbs variations in shape (such as unevenness). On the other hand, since the heat radiation material 201 is made of a material with low elasticity, the force with which the cooling member 23 urges the power semiconductor element 63 upward can be considerably reduced. This also makes it possible to relieve stress on the fixed portion 91.

A modification of the above-mentioned inverter device mounting structure 10 will be described with reference to FIGS. 7 and 8.

<Modified example>
As shown in FIG. 7(A), a heat dissipating material filling section 210 may be provided on the upper surface 23U of the cooling member 23 (bottom section 22B of the circuit housing section 22). The heat dissipating material filling portion 210 has a concave shape into which the heat dissipating material 201 can be filled. When the heat dissipation material 201 has high fluidity, the heat dissipation material 201 can be retained in a predetermined region by filling the heat dissipation material filling portion 210.

Further, as shown in FIG. 7(B), the first movement regulating member 100 includes not only a board engaging part (first engaging part) 103A that protrudes from the pedestal part 104 in the direction (upward) of the circuit board 8, but also Another engaging portion (second engaging portion) 103B may be provided that protrudes from the portion 104 toward the cooling member 23 (downward). In this case, it is preferable that the second engaging portion 103B engages with, for example, the fixing hole 63H of the power semiconductor element 63.

Moreover, as shown in FIG. 8(A), the power semiconductor element 63 may be an intelligent power module (IPM). FIGS. 8(B) and 8(C) are plan views of the IPM 63 viewed from the heat sink 64 side. The IPM is a power semiconductor element in which a switching element such as a power MOSFET or an insulated gate bipolar transistor (IGBT) for controlling electric power, a driving circuit thereof, and a self-protection function are incorporated into one resin package 63P.

FIG. 8(D) is an example in which the first movement regulating member 100 is provided with a first engaging portion 103A projecting upward and a second engaging portion 103B projecting downward, similar to FIG. 7(B). As shown in FIGS. 8(B) and 8(C), the IPM 63 has a known configuration, and for example, a fixing hole 63H and a notch 63D for fixing are provided in the resin package 63P. In this embodiment, the IPM 63 is not pressed and fixed against the cooling member 23 using screws, leaf springs, etc., but it is preferable that the second board engaging portion 103B is engaged with these fixing holes 63H and notches 63D. . Further, the cooling member 23 shown in FIG. 8 may include a heat dissipating material filling part 210 as shown in FIG. 7(A).

<Mounting structure of inverter device/Second embodiment>
A second embodiment of the mounting structure for the inverter device 9 will be described with reference to FIGS. 9 to 12.

In the second embodiment, a plurality of (for example, six) power semiconductor elements 63 constituting an inverter circuit section 6 are integrated to form an inverter circuit module, and the inverter circuit module is further integrated with a circuit board 8. This is an example.

<Inverter circuit section>
The configuration of the inverter circuit section 6 will be explained with reference to FIG. FIG. 9 is a diagram illustrating the inverter circuit section 6 (power semiconductor module 63'), and FIG. 9A is an external perspective view of the power semiconductor module 63'. FIG. 2B is a diagram showing a part of the inverter circuit section 6 (inverter device 9), and is a schematic cross-sectional view corresponding to the section taken along the line AA in FIG. Hereinafter, configurations that are different from the first embodiment will be mainly described, and detailed descriptions of configurations similar to the first embodiment will be omitted.

The power semiconductor module 63' includes six power semiconductor elements 63, a base plate 56 on which these are integrally placed, and a base plate 56 that covers at least a portion of the power semiconductor elements 63 and the power semiconductor elements 63 and the base plate 56. It has an insulating resin part 67 that integrates the. The power semiconductor element 63 is the same as in the first embodiment.

The base plate 56 is, for example, a substantially rectangular flat plate made of a highly heat dissipating metal (for example, aluminum), and has six power semiconductor elements 63 arranged in two rows of three on one surface (mounting surface) Sf3. It will be placed. The terminals 63C of the power semiconductor elements 63 in each column are adjacent to each other approximately in the center of the base plate 56. The power semiconductor elements 63 for each row are integrated (molded) with the insulating resin portion 67 and are also integrated with the base plate 56. The insulating resin portion 67 is, for example, a resin material that can be injection molded, and here, as an example, it is a thermoplastic resin material. In this embodiment, the power semiconductor element groups 631 and 632 are formed by injection molding (hot melt) of a thermoplastic resin material to integrate three power semiconductor elements 63 into a set so as to cover at least a portion of these elements. These are then fixed to the base plate 56. Alternatively, the base plate 56 is fixed to the power semiconductor element groups 631, 632 (power semiconductor elements 63). In this case, "fixing" (fixing with a resin material) means that when the softened (or liquefied) resin hardens, it contacts (interposes) both the power semiconductor element 63 and the base plate 56 to integrate them. It means to do something. That is, at least four side surfaces SS of the power semiconductor element 63 are surrounded by resin that collectively constitutes the insulating resin portion 67, and the resin continues up to the base plate 56. In this embodiment, the three power semiconductor elements 63 constituting each of the power semiconductor element groups 631 and 632 are surrounded by resin that collectively constitutes the insulating resin part 67 at least four side surfaces SS thereof, and the resin is continuous up to the base plate 56, but the plurality of power semiconductor elements 63 do not need to be integrated. That is, any configuration is sufficient as long as at least one power semiconductor element 63 is integrated with the base plate 56.

Furthermore, as shown in FIG. 9B, an insulating resin sheet 69 (for example, a silicone resin sheet) is interposed between the power semiconductor element groups 631 and 632 and the base plate 56. The heat sink 64 exposed on the lower surface DS of the resin package 63P of each power semiconductor element 63 comes into contact with the insulating resin sheet 69, and comes into close contact with the base plate 56, which has good flatness, through this. Furthermore, a portion of the terminal 63C of each power semiconductor element 63, including the lead-out portion from the resin package 63P, is covered with the insulating resin portion 67, but the other portion, including the tip portion, is exposed from the insulating resin portion 67.

Further, bolt insertion holes 86 through which bolts for fixing the inverter circuit section 6 to the housing 2 can be inserted are provided at multiple locations (four locations in this example) around the base plate 56, and each A sleeve component 65 whose internal space communicates with the bolt insertion hole 86 is provided upright. The sleeve component 65 is also integrated with the power semiconductor element 63 and the base plate 56 by an insulating resin portion 67.

Further, in the second embodiment, the insulating resin portion 67 constitutes a first position regulating member (first position regulating portion) 150. The shape of the first position regulating member 150 is generally the same as that of the first embodiment, and includes a pedestal portion 151 and a board engaging portion 152 that protrudes upward from the pedestal portion 151 in the motor axis direction. In this case, the pedestal part 151 is provided in a substantially truncated conical shape that protrudes upward in the motor axial direction from the upper surface 67U of the resin part of the power semiconductor element group 631, 632, and extends further upward in the motor axial direction from the upper surface of the pedestal part 151. A substantially cylindrical substrate engaging portion 152 is provided so as to protrude. A step portion (shoulder portion) between the pedestal portion 151 and the board engaging portion 152 becomes a board abutting portion 153 that comes into contact with the circuit board 8. In this case, the pedestal part 151 is provided as a part of the insulating resin part 67, and there is no package contacting part that directly contacts the power semiconductor element 63 on the lower surface of the pedestal part 151.

The sleeve component 65 is a cylindrical member made of metal (for example, aluminum), and it is preferable that the sleeve component 65 is a cylindrical member made of metal (for example, aluminum), and its surface is textured so that it has high adhesion to the insulating resin portion 67. Further, the plurality of sleeve components 65 in the inverter circuit section 6 have the same height (axial length), and are arranged at a distance from each other around the base plate 56 (in this case, approximately at the four corners). The sleeve component 65 is arranged so that its axial direction is parallel to the motor axial direction, and the height t4 from the surface of the base plate 56 to the upper end of the sleeve component 65 is equal to the upper surface 67U of the resin part of the power semiconductor element groups 631 and 632. , or the resin package 63P of the power semiconductor element 63, whichever is greater, is higher than the height t5. Further, the height t4 of the sleeve component is lower than the height t6 from the surface of the base plate 56 to the board contacting part 102 of the pedestal part 104.

In this embodiment, a plurality of power semiconductor elements 63, a base plate 56, and a sleeve component 65 are integrally fixed to each other by, for example, injection molding of thermoplastic resin to form a power semiconductor module that is a set of electronic components. 63', and the insulating resin portion 67 constitutes the first position regulating member 150. The first position regulating member 150 may be provided at least for each insulating resin portion 67 (at least one for each of the power semiconductor element groups 631 and 632). In addition, since it can be molded as a part of the insulating resin part 67 by resin injection molding or the like, it is easier to assemble than in the case where the first position regulating member 100 is disposed on each of the power semiconductor elements 63 as in the first embodiment. complexity is reduced.

As shown in FIG. 9(B), the power semiconductor module 63' and the circuit board 8 are integrated in advance through a subline or the like to form an inverter device 9. The circuit board 8 contacts and is supported by the board contact portion 153, and the power semiconductor element 63 and the circuit board 8 are maintained at a predetermined distance t1 in the motor axis direction (vertical direction in the drawing).

In this way, the first movement restricting member 150 functions as a spacer between the power semiconductor element 63 and the circuit board 8, maintains the distance t1 between the two, and restricts them from moving in a direction closer to each other than the distance t1. do. Although not shown in FIG. 9B, the circuit board 8 is also provided with desired electronic components such as the filter circuit section 7 as appropriate.

<Manufacturing method of inverter circuit section>
An example of a method for manufacturing the inverter circuit section 6 in the second embodiment will be described with reference to FIG. 10. 10(A) to 10(D) are external perspective views showing an example of a method for manufacturing the inverter circuit section 6. FIG. In the description of FIG. 10, the base plate 56 side will be described as the lower side and the circuit board 8 side will be described as the upper side.

First, as shown in FIG. 10(A), an insulating resin sheet 69 is placed in a predetermined area of the mounting surface Sf3 of the base plate 56, and a plurality of (six in this case) three power semiconductor elements 63 are placed thereon. are placed in two rows as one set (FIG. 10(B)). Then, for example, by injection molding of a thermoplastic resin material, an insulating resin portion 67 that integrates the three power semiconductor elements 63 and the base plate 56 is formed. (Figure 10(C)). Further, the sleeve component 65 is also integrated with the power semiconductor element 63 and the base plate 56 by the insulating resin portion 67, and the first movement regulating member (first movement regulating portion) 150 is molded.

The power semiconductor module 63' manufactured in this way is connected to the circuit board 8. That is, as shown in FIG. 10(D), the circuit board 8 is arranged so that the mounting surface Sf3 of the base plate 56 and the second surface Sf2 of the circuit board 8 face each other. Engagement holes 88 are provided in a predetermined region of the circuit board 8 at positions corresponding to the two board engagement portions 152 of the first position regulating member 150 (see FIG. 9(B)).

Then, the board engaging portion 152 is inserted into the engaging hole 88 to bring the second surface Sf2 of the circuit board 8 into contact with the board abutting portion 153 of the first position regulating member 150. The circuit board 8 is supported by the board contact portion 153 and maintained at a distance t1 from the upper surface US of the power semiconductor element 63 (the upper surface 67U of the resin portion of the power semiconductor module 63') (see FIG. 9B).

Further, the circuit board 8 is provided with a terminal insertion hole 83 (see FIG. 9(B)), and the tip of the terminal 63C of the power semiconductor element 63 is inserted into the terminal from the second surface Sf2 side of the circuit board 8. It is led out to the first surface Sf1 side through the insertion hole 83.

In this state, the wiring (not shown) provided on the second surface Sf2 of the circuit board 8 and the terminal 63C of the power semiconductor element 63 are electrically fixed (connected) using the conductive adhesive 90. In this way, the inverter circuit section 6 is formed. Although not shown here, the terminals (leads) of the electronic components constituting the filter circuit section 7 are inserted through the terminals from the second surface Sf2 of the circuit board 8 in another area of the circuit board 8. It is led out to the first surface Sf1 side through the hole, and is electrically fixed (connected) to the wiring (not shown) provided on the second surface Sf2 of the circuit board 8 with the conductive adhesive 90, thereby forming a filter circuit. Section 7 is formed. In this way, an inverter device 9 is formed in which the inverter circuit section 6 and the filter circuit section 7 are integrated (modularized) on a single circuit board 8.

<How to install an inverter device/Second embodiment>
A method of attaching the inverter device 9 configured as described above (FIGS. 9 and 10) to the cooling member 23 will be described with reference to FIGS. 11 and 12.

As shown in FIG. 11A, first, a heat dissipating material 201 is provided on the upper surface 23U of the cooling member 23 by coating or the like. The heat dissipation material 201 is the same as that in the first embodiment. The heat dissipation material 201 is applied to the upper surface 23U of the cooling member 23 at a position that faces at least the heat dissipation plate 64 of the power semiconductor element 63 and can come into contact with the base plate 56.

Further, the second movement regulating member 160 is also provided in the second embodiment. The second movement restriction member 160 is, for example, a sleeve component that is hollow inside and allows the bolt 85 to be inserted therethrough, and the second movement restriction member 160 has a cooling member contact portion 161 and a substrate contact portion 162. In this example, the second movement restricting member 160 is placed at a position surrounding the screw hole 26 of the cooling member 23 .

The sleeve part 65 of the power semiconductor element module 63' is integrated with the power semiconductor element 63 and the base plate 56 by the insulating resin part 67, but the second movement regulating member 160 is integrated with the insulating resin part 67 and the sleeve part 65. is a separate body (a part independent from both) and is not fixed to either.

Then, as shown in FIG. 11(B), the inverter device 9 is housed in the circuit housing section 22. The second movement regulating member 160 is inserted into the sleeve component 65 of the power semiconductor element module 63', and the second surface (lower surface DS, heat sink 64) of the power semiconductor element 63 is connected to the insulating resin sheet 69, the base plate 56 and the cooling member 23 via the heat dissipating material 201. Note that after the inverter device 9 is accommodated in the circuit housing portion 22, the second movement restricting member 160 may be inserted into the sleeve component 65 of the power semiconductor element module 63'.

As shown in FIG. 6C, the height t6 of the second movement restricting member 160 is greater than the height t4 of the sleeve component 65. As a result, when the inverter device 9 is attached to the cooling member 23 (when housed in the circuit accommodating portion 22), the circuit board 8 is supported by the second movement regulating member 110, and the cooling member 23 and the circuit board 8 are It is maintained at a predetermined distance t6 (height of the second movement regulating member 160) in the axial direction (vertical direction in the drawing). That is, the second movement restriction member 160 functions as a spacer between the cooling member 23 and the circuit board 8, maintains the predetermined distance t6 between the two, and restricts them from moving in a direction closer to each other than the distance t6.

The height t6 of the second movement regulating member 160 is such that when the circuit board 8 is supported, the lower surface 56DS and the upper surface 23U of the base plate 56 are not in direct contact with each other, and the lower surface 56DS of the base plate 56 is in contact with the heat dissipating material 201. It is set to maintain direct contact only with the As a result, a very small gap is created between the base plate 56 and the cooling member 23 due to the second movement restricting member 160.

The heat dissipating material 201 fills this gap, whereby the lower surface 56DS of the base plate 56 reliably and sufficiently contacts the heat dissipating material 201, and can make surface contact with the cooling member 23 via this. In other words, the heat dissipation material 201 is a means for efficiently transmitting the heat generated in the heat dissipation plate 64 to the cooling member 23 via the insulating resin sheet 69 and the base plate 56, and in addition, the heat dissipation material 201 is a means for efficiently transmitting the heat generated in the heat dissipation plate 64 to the cooling member 23 via the insulating resin sheet 69 and the base plate 56. It fills the extremely small gap that occurs between the cooling member 23 and functions as a means for absorbing assembly tolerances and variations in surface shape between the two (such as unintended irregularities).

That is, the material and thickness (coating thickness) of the heat dissipating material 201 are appropriately selected in consideration of the ability of the heat dissipating material 201 to perform these functions and the shape of the component.

Then, as shown in FIG. 12A, bolts 85 are inserted into bolt insertion holes 86 provided in the circuit board 8 and fastened and fixed to the screw holes 26 of the cooling member 23. In this example, the second movement restricting member 160 is arranged so as to communicate with both the bolt insertion hole 86 and the screw hole 26 of the cooling member 23. That is, the bolt 85 is inserted into the second movement regulating member 160 and fastened to the screw hole 26 . At this time, the circuit board 8 is supported by the second movement regulating member 150 without direct contact between the base plate 56 and the cooling member 23, and the gap created between the base plate 56 and the cooling member 23 is filled with the heat dissipating material 201. Assembly tolerances and surface shape variations between the two are absorbed.

That is, although the circuit board 8 is fastened and fixed to the cooling member 23 with bolts 85, the circuit board 8 and the power semiconductor element 63 (power semiconductor module 63') are directly pressed against the cooling member 23 due to the fastening force. It will never happen. Since the heat radiation material 201 is a material with a small elastic force, the reaction force from the cooling member 23 (upward reaction force in the motor axis direction) is extremely small. Therefore, the stress generated between the terminal C63 of the power semiconductor element 63 and the fixed portion 91 of the circuit board 8 can be alleviated.
Therefore, the stress generated in the fixed portion 91 between the circuit board 8 and the terminal 63C of the power semiconductor element 63 can be alleviated, and the occurrence of cracks can be suppressed.

Further, the second surface (lower surface DS, heat sink 64) of the power semiconductor element 63 is in sufficient surface contact with the upper surface of the cooling member 23 via the insulating resin sheet 69, the base plate 56, and the heat sink 201. Improves heat dissipation.

In this way, the inverter device 9 can be detachably attached to the cooling member 23. Here, the cooling member 23 described above is a part of the casing 2 in which the motor of the electric compressor 1 is housed, as shown in FIG. Therefore, the electric compressor 1 can be assembled using the above method. That is, the inverter device 9 is manufactured by integrating the circuit board 8, the inverter circuit section 6, and the filter circuit section 7 in advance through a sub-line or the like. Then, the inverter device 9 is housed in the circuit housing section 22 defined within the housing 2, and the circuit board 8 is fixed to the housing 2 with bolts 85 using the method described above, and the electric compressor 1 is assembled.

As shown in FIG. 12, after the board engaging part 152 of the first movement regulating member 150 is engaged with the circuit board 8, the board engaging part 152 is fixed to the circuit board 8 by heat caulking. You can also do this. Further, in the second embodiment, the plurality of power semiconductor elements 63 may be integrally molded using the insulating resin portion 67 without providing the base plate 56.

Further, the pedestal portion 104 of the first movement regulating member 100 may be formed into a plate shape, for example. The plate-shaped pedestal part 104 has a shape that can collectively cover (hold) a plurality of independent (non-integrated) power semiconductor elements 63 (for example, three or six) from above, One or more engaging portions 103 (first engaging portion 103A, second engaging portion 103B) protruding from the surface may be provided.

Further, in the above example, an IGBT is used as an example of a switching element, but the switching element is not limited to this, and may be an SiC element, a MOSFET, or the like.

It should be noted that the electric compressor 1 of the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be used in the field of electric compressors.

1 Electric compressor 2 Housing 3 Motor 3a Winding 4 Rotating shaft 5 Compression mechanism 6 Inverter circuit section 7 Filter circuit section 8 Circuit board (printed board)
9 Inverter device 21 Housing 22 Circuit housing portion 23 Partition wall (cooling member)
56 Base plate 63 Power semiconductor element 63C Terminal 63' Power semiconductor element module 63H Fixing hole 63P Resin package 64 Heat sink 65 Sleeve part 67 Insulating resin part 67U Resin part upper surface 69 Insulating resin sheet 70 Filter circuit part 83 Terminal insertion hole 85 Bolt 86 Bolt insertion hole 88 Engagement hole 90 Conductive adhesive 91 Fixing part 100 First movement regulating member 102 Board abutting part 103 Board engaging part 104 Pedestal part 110 Second movement regulating member 151 Pedestal part 152 Board engagement Part 153 Board contact part 161 Cooling member contact part 162 Board contact part 201 Heat dissipation material 210 Heat dissipation material filling part

Claims (9)

An inverter device mounting structure for attaching an inverter device to a cooling member,
The inverter device includes:
A power semiconductor element,
a circuit board disposed opposite to the first surface of the power semiconductor element;
a conductive adhesive that electrically fixes the circuit board and the terminal of the power semiconductor element;
a movement regulating member that maintains the power semiconductor element and the circuit board at a predetermined distance;
a second surface of the power semiconductor element facing the cooling member via a heat dissipating material, and attaching the circuit board to the cooling member;
A mounting structure for an inverter device, characterized by the following. further comprising another movement regulating member capable of maintaining a predetermined distance between the circuit board and the cooling member;
The inverter device mounting structure according to claim 1, characterized in that: The movement regulating member is not fixed to at least the power semiconductor element, and comes into contact with a portion of each of the power semiconductor element and the circuit board.
The inverter device mounting structure according to claim 1, characterized in that: The movement regulating member has a pedestal portion that can come into contact with a portion of each of the power semiconductor element and the circuit board, and an engaging portion that protrudes from the pedestal portion and engages with the circuit board.
The inverter device mounting structure according to claim 1, characterized in that: The movement regulating member has another engaging part that protrudes from the base part and engages with the power semiconductor element.
5. The inverter device mounting structure according to claim 4. The heat dissipating material is a fluid and/or flexible material,
The inverter device mounting structure according to claim 1, characterized in that: It has a mounting structure for an inverter device according to any one of claims 1 to 5,
An electric compressor with a built-in motor inside the housing,
the cooling member is a part of the casing;
An electric compressor characterized by: accommodating the inverter device in a circuit accommodating section partitioned within the casing;
The electric compressor according to claim 7, characterized in that: The cooling member is a bottom surface of the circuit accommodating portion, and the bottom surface is provided with a filling portion of the heat dissipation material.
The electric compressor according to claim 8, characterized in that:

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